A wide variety of pesticides are commonly used in agronomic and horticultural pursuits. As used herein the term "pesticide" means any chemical compound or composition which displays biological activity in an agricultural field site or at any locus where control of biological growth is desired. The biological activity or control contemplated herein includes all forms of growth modification, ranging from regulation and retardation to killing, and extends to all forms of plant and animal life found in an agricultural environment during some time during the pest's life cycle. Pesticides within this invention include anti-foulants, plant growth regulants, soil fumigants, molluscicides, insecticides, herbicides, fungicides, rodenticides, nematocides, algicides, predator control agents, and insect and animal repellents. Additional biologically active compounds can also be present in admixture with the primary ingredient, such as synergists, antidotes, fertilizers, soil life extenders, and additional pesticides.
The term "biologically effective amount" is used herein to denote any quantity of pesticide, pesticide composition, concentrate, or emulsion, which when applied to an agricultural site in any conventional manner causes the occurrence of one or more of the biological effects mentioned above. As further explained in the latter portion of this specification, the quantity of pesticide applied in a given situation will depend on the pesticide itself, on the type of biological activity inherent in the pesticide, and the degree of such activity sought to be achieved. The selection of the proper quantity to be applied, however, is within the expertise of one skilled in the art.
In general if handled carelessly, improperly or in disregard of directions, the pesticide, depending upon its toxicity, may present a hazard to those handling the pesticide whether in packaging it for sale, handling it for shipment, mixing it for field application or applying it in the field. The toxicity of the pesticide will vary depending upon a number of factors, including the inherent toxicity of the pesticide substance at its site of biological action. Various physical properties of the pesticide including the hydrophilic-lipophilic balance of the pesticide affect the adsorption to and absorption by various tissues of the person handling the pesticide compound, and thus affect the toxicity of the compound to the person handling it.
Some pesticides, such as the chlorinated hydrocarbon carbamate insecticides and the organophosphate pesticide compounds, including pyrethroids, phosphonate, organophosphate and organothiophosphate compounds present a problem of dermal toxicity to persons handling these substances. Thus, it is desirable to develop formulations for these pesticide compounds that reduce the dermal toxicity of the compound to persons handling them yet still preserve the pesticidal effectiveness of the compound as applied to the pest or the locus where the pest may be found.